A silver halide color photographic material generally has silver halide emulsion layers sensitive to the three primary colors of red, green, and blue and by a so-called subtractive color process, i.e., a process of coloring each of the three kinds of couplers in the silver halide emulsion layers in the relation of a complementary color with the color sensitive to each emulsion layer, color images are formed.
The color images obtained by photographic processing the silver halide color photographic material are generally composed of azomethine dyes or indianiline dyes formed by the reaction of the oxidation product of an aromatic primary amine color developing agent and couplers.
The color images thus obtained are not always stable to light, humidity, and heat and hence when the color images are exposed to light for a long period of time or stored under the conditions of a high temperature and a high humidity, the color images are faded or discolored to deteriorate the color images.
Such fading and discoloring of color images are a defect which can be said to be a fatal defect for a recording material. As a method of removing such a defect, the development of couplers giving dyes having a high fastness, the use of fading inhibitors, the use of ultraviolet absorbents for preventing the deterioration of color images by ultraviolet rays, etc., have been proposed.
In these proposals, the effect of inhibiting the deterioration of images with a fading inhibitor is large. For this purpose, it is known to add hydroquinones, hindered phenols, catechols, gallic acid esters, aminophenols, hindered amines, chromanols, indanes, the ethers or esters obtained by silylating, acylating, or alkylating the phenolic hydroxy groups of the foregoing compounds, and further metal complexes, etc.
However, these compounds may certainly have the effect as an inhibitor of the fading and discoloring of color images but the effect obtained by these compounds is yet insufficient for meeting the requirement by customers who require a higher image quality. Also, some of these compounds greatly color the background portions, cause coloring (hereinafter, is referred to as fog) at unexposed portions, cause coloring hindrance of couplers, and also cause color turbidity by forming dyes by causing a reaction with the oxidation product of a color developing agent as color development to give bad influences on the photographic characteristics. Thus, these are not satisfactory compounds. Furthermore, some of these compounds cause inferior dispersion or form fine crystals after coating the emulsion thereof, and hence they have not yet given generally excellent effects for color photograph.
Also, the compounds having the structures similar to the chroman structure and coumaran structure or the compounds having a bisphenolic structure are known as an image deterioration inhibitor. These compounds all show a fading inhibition effect. But they are insufficient for the strong requirement for obtaining fastness of color images. Moreover, some of these compounds color the background to yellow (yellow stain) with the passage of time and form dyes by causing a reaction with the oxidation product of a color developing agent at developing to cause a color turbidity. Therefore, these compounds are not excellent ones.